No. These are static QR codes: the content is encoded directly into the image, so they work forever and do not depend on ChungDoi or any middleman. As long as the link or information inside stays valid, the code keeps scanning, even years later.

Besides a plain link or text, you can make a WiFi QR so guests join the venue network with one scan, a contact card (vCard) for the couple, a calendar event QR so guests add your wedding date to their phone, and a phone-number QR for quick calls. Pick the type at the top of the tool; every type is built right in your browser and nothing is uploaded.

This tool makes clean, logo-free codes for the fastest, most reliable scanning. A logo in the center hides part of the data and forces scanners to rely on error correction, which makes scans fail more often when printed small or in low light.

Use PNG to share the code via chat apps or to drop it into an image. Use SVG for printing: it is a vector image that stays perfectly sharp at any size, so a print shop can scale it onto a card or a large standee without pixelation.

Yes. The QR code is generated entirely in your browser; the content you type is never uploaded to a server. That makes it safe even for account numbers, phone numbers, or private links.

A good rule of thumb: at least 2-3 cm per side for a handheld card, and larger if people scan from a distance (a standee or a screen). Keep a white margin (quiet zone) around the code, and use the Large (2048px) download if you plan to print.